Learn about this topic in these articles:

development by Breguet

...principal watchmaker of the empire. Among Breguet’s many inventions and innovations were the overcoil, an improvement of the balance spring that was incorporated into many precision watches, and the
tourbillon, an improvement that rendered the escapement immune to errors caused by the changing position of the watch while being carried. Breguet succeeded Pierre-Louis Berthoud as the official...